Ammonia Refrigeration Final Exam Study Guide
Questions and Correct Answers
,____ is the heat energy required to cause a liquid to become a vapor - CORRECT ANSWER
latent heat of vaporization
____'s are used to measure the quality of heat energy - CORRECT ANSWER BTU
-40°F is equal to? - CORRECT ANSWER 40°F
100°C equals - CORRECT ANSWER 212°F
A "King" valve is a ____ - CORRECT ANSWER receiver inlet valve
A 3% concentration of ammonia equals? - CORRECT ANSWER 3,000 PPM
A crankcase oil heater is to be on when the ____ is off - CORRECT ANSWER compressor
A reciprocating compressor is running with an actual discharge temperature lower than
theoretical discharge temperature. What could this indicate? - CORRECT ANSWER liquid in
the suction vapor
A slight leak in a fitting on a HCFC/22 system causes the Halide torch flame to turn ____ -
CORRECT ANSWER green
A surge drum on a flooded evaporator is used for? - CORRECT ANSWER separating vapor
from liquid
A vapor cannot be ____ - CORRECT ANSWER subcooled
Absolute pressure is the pressure read by a gauge, plus the ____ atmospheric pressure -
CORRECT ANSWER ambient
Air cooled condensers usually have higher head pressures then ____ condensers - CORRECT
ANSWER evaporative
, Ammonia is what on the PH scale? - CORRECT ANSWER 11.6
An evaporative condenser uses water and ____ - CORRECT ANSWER air
An increase in the air resistance through an evaporator results from placing fins ____
together - CORRECT ANSWER closer
An induced draft fan draws air through the ____ - CORRECT ANSWER coils
As long as a technician does not perform work on proportions of a system containing
refrigerant, they do not need to be ____ - CORRECT ANSWER certified
As the ratio between the evaporator and condensing pressure increases ____ - CORRECT
ANSWER the theoretical discharge temperature increases
Before the formation of liquid occurs in the condenser, the condenser's refrigerant vapor
must be ____ - CORRECT ANSWER desuperheated
Brines maybe preferred to water because they have ____ freezing points - CORRECT
ANSWER lower
Compared to other freezers, blast freezer applications require ____ time to freeze the
product - CORRECT ANSWER less
Compression ends on a rotary vane or rotary screw compressor when the vapor reaches the
____ point or when the vapor reaches the discharge port - CORRECT ANSWER discharge
Convection is the transfer of ____ - CORRECT ANSWER heat through a material or
substance
Copper tubing is never used with? - CORRECT ANSWER R717
Questions and Correct Answers
,____ is the heat energy required to cause a liquid to become a vapor - CORRECT ANSWER
latent heat of vaporization
____'s are used to measure the quality of heat energy - CORRECT ANSWER BTU
-40°F is equal to? - CORRECT ANSWER 40°F
100°C equals - CORRECT ANSWER 212°F
A "King" valve is a ____ - CORRECT ANSWER receiver inlet valve
A 3% concentration of ammonia equals? - CORRECT ANSWER 3,000 PPM
A crankcase oil heater is to be on when the ____ is off - CORRECT ANSWER compressor
A reciprocating compressor is running with an actual discharge temperature lower than
theoretical discharge temperature. What could this indicate? - CORRECT ANSWER liquid in
the suction vapor
A slight leak in a fitting on a HCFC/22 system causes the Halide torch flame to turn ____ -
CORRECT ANSWER green
A surge drum on a flooded evaporator is used for? - CORRECT ANSWER separating vapor
from liquid
A vapor cannot be ____ - CORRECT ANSWER subcooled
Absolute pressure is the pressure read by a gauge, plus the ____ atmospheric pressure -
CORRECT ANSWER ambient
Air cooled condensers usually have higher head pressures then ____ condensers - CORRECT
ANSWER evaporative
, Ammonia is what on the PH scale? - CORRECT ANSWER 11.6
An evaporative condenser uses water and ____ - CORRECT ANSWER air
An increase in the air resistance through an evaporator results from placing fins ____
together - CORRECT ANSWER closer
An induced draft fan draws air through the ____ - CORRECT ANSWER coils
As long as a technician does not perform work on proportions of a system containing
refrigerant, they do not need to be ____ - CORRECT ANSWER certified
As the ratio between the evaporator and condensing pressure increases ____ - CORRECT
ANSWER the theoretical discharge temperature increases
Before the formation of liquid occurs in the condenser, the condenser's refrigerant vapor
must be ____ - CORRECT ANSWER desuperheated
Brines maybe preferred to water because they have ____ freezing points - CORRECT
ANSWER lower
Compared to other freezers, blast freezer applications require ____ time to freeze the
product - CORRECT ANSWER less
Compression ends on a rotary vane or rotary screw compressor when the vapor reaches the
____ point or when the vapor reaches the discharge port - CORRECT ANSWER discharge
Convection is the transfer of ____ - CORRECT ANSWER heat through a material or
substance
Copper tubing is never used with? - CORRECT ANSWER R717
